Shock absorbing deive for earth boring apparatus



9 v H. R. SMITH 2.210506 SHOCK ABSORBING DRIVE FOR EARTH BORING APPARATUS Filed June 24, 1939 3 Sheets-Sheet l Q4 V 7p 16 a 22 6 28 1'1 III II INVENTOR fiyifiau Jam ATTORNEY 6 z- 1940- 'H. R. SMITH 2.210.506

SHOCK ABSORBING DRIVE FOR EARTH BORING APPARATUS Filed June 24, 1939 3 Sheets-Sheet 2 FIG.2.

/2M v w ATTORN EYJ Aug. 40- H. R. SMITH 2.210.506

SBQCK ABSORB ING DRIVE FOR EARTH BORING APPARATUS Filed June 24, 1939 3 Sheets-Sheet 3 INVENTOR v IVE/7111A R SAI/T/f ATTORNEYS UNITED sTATss r SHOCK ABSORBING DRIVE FOR EARTH BORING APPARATUS Herman R. Smith, Douglaston, N. Y., assignor to Raymond Concrete Pile Company, New York, N. Y., a corporation of New Jersey Application June 24, 1939, Serial No. 281,017

2 Claims. (01. 255-19) This invention pertains to apparatus for boring cup-shaped receptacle 44, axially horizontal and into the earth, with particular reference to imadapted to contain a resilient member, usually in proved means for rotating a drill stem and bucket the form of a substantially cylindrical rubber under very severe service conditions. For exambumper Mi, which normally projects slightly from 5 ple, the presence of coarse sand, gravel and boulthe open end of cup 44. 5 ders in the ground often subjects the rotary Resting on plate 40 is another annular plate equipment to very severe punishment. The reor collar designated 48,] the inner circumference sistance encountered momentarily stalls the of which is provided with slots to slidalbly en-. bucket, with the result that the drill stem and gage the three splines 50 extending lengthwise shafting of the rotary equipment twist until the of drill stem I2 and integral therewith. The 10 torque is sufficient to overcome the resistance, outer circumference of plate 48 has three radial whereupon the bucket rotates suddenly for a proj c i ns c sh pr vi d Wi h a p d 54 small part of a revolution under the drive of the adapted to take the thrust of one of the resilient motor plus the spring effect of the wound-up bumpers liHFig. 3).

drill stem and shafting. Then the stalling, wind- Bolted to each part 22 of plate M) is a clip 55 ing-up and letting-go cycle repeats indefinitely adapted to keep plate to in contact, and concenand at times with machine gun rapidity until the trio with, plate 48. Plate 48 is provided with a vibration and pounding results in failure of some p of lifting rings 58 (Figs. 1, 3 and. 4)

part of the apparatus. The method of operatively connecting ring 38 An object of the invention is to prevent the and drive spindle 23 is not ind c ted in g. 20 above difficulties by providing driving mechanism ut s illust ate i s- 5 d The 1 of including means for overcoming the above diffir y Spindle 23 is p d W th four slots 60 cultiesh (Figs. 5 and 6) each engaged by a lug 62 on the Further and other objects and advantages will inside of ring 38. Slots 60 are undercut as indi- 25 be apparent from the specification and claims, ate at 54 gd lugs 62 are shaped as at 25 andfrom the accompanying drawings which ilto to engage h nd u h r by pr ve n lustrate what is now considered a preferred emthe l f m n v r en ly r n fr m the slots.

FICE Y bodiment of the invention. In operation, with the parts rotating in the di- Figure 1 is a, general iew of the complet rection indicated by the arrow in Fig. 3, the ml)- apparatus. "oer cushions to compress more or less as the load 30 Fig. 2 is an enlarged View of that portion of varies, with the result that practically all of the the apparatus which includes the resilient drive. noise and most of the vibration of the dr l Fig. 3 is a view on line 33 of Fig. 1. rig is eliminated. The bumpers also serve to Fig. 4 is similar to Fig. 3, but with the parts cushion the blow when the core barrel or exin different relative positions. oavating bucket encounters any sudden resist- 35 Fig. 5 is a cross-section on line 5-5 of Fig. 2. ance severe enough to stall the motors which, Fig 6 is a View in th di ti n f 6.4; of under certain conditions, occurs at frequent in- Fig 5 tervals. When such a stall occurs it has been Referring to Fig. 1, HJ represents a bucket or found that the flywheel effect of the motors stores core barrel attached to, and rotated by, the holp mo e e y than What is delivered y a p 40 low drill stem l2 which in turn is rotated by driving hammer at the moment of p but it gear M in a manner to be described. Gear l 4 is has been found in service that the present invendriven by one or more motors it through gearing tion so greatly reduces the stresses on shafting such as spur pinion l8, gear 20, bevel pinion 22, and other parts of the apparatus, that breakage is bevel gear 24, and spur pinion 26 (Fig. 1). practically eliminated. 5

Referring to Fig, 2, gear 14 is integral with the Occasionally, the rotary table is driven in a upwardly extending annular drill spindle 28 reverse direction, and to meet that condition pmwhich is supported for rotation on bearings 36, J'ections it on ring 40 areprovided with stops 68 32 and 34 in a shell 36 integral with the frameadapted for engagement by lugs ill on projections k of th achi e. 52 of ring 48 (Fig. 4). Since the service is very 50 Mounted on top of member 28 and driven light in this reverse motion, no rulbber cushions thereby in a manner which will be described, is a or bumpers are necessary. ring 38. Welded to ring 38 is an annular plate It is to be understood that the invention is not 40 having three projecting portions 42* (Figs. 3 limited to the specific embodiment herein illusand 4) upon each of which is rigidly mounted a trated and described, but may be used in other 55 2. In apparatus for boring into the ground, in combination, a vertical drill stem, a collar surrounding said stem and slidable therealong, means preventing rotation of said collar relatively to said stem, a ring supported for rotation about said stem adjacent said collar, means for rotating said ring, and a plurality of rubber bumpers on said ring and adapted to engage said collar and rotate said stem through the instrumentality of said collar.

HERMAN R. SMITH. 

